1.This link is only the shaft and switches for mechanical keyboard,no keyboard included.It's 3 pin switches.
2.It can support SMD leds.
If you want to install 2 pin 4 pin switch leds, you need to solder led at first onto PCB and then put on switches on
3.TTC bluish white is tacto;e switches,actuation weight is around 42gf.
4.The lifetime is around 100 million times.